So I recently started trading with a much larger position and am skeptical as to what might be going on causing me to take extra losses. I trade intraday and follow momentum whichever direction that might be.Im currently with TD Ameritrade and am possibly going to be moving to another broker (currently looking and comparing). Recently I've noticed more and more that if I take a position on lets say "SPY" as soon as I place my order it almost immediately starts going against me; so my question is this, is it because of my position sizing, my broker, mm, or do I just have to change strategy to trade with a much larger position?